1. Department of Botany; Biodiversity Research Centre; University of British Columbia; 3529-6270 University Blvd. Vancouver British Columbia Canada V6T 1Z4
2. School of Environmental and Rural Science; University of New England; Meredith Rd. Armidale NSW 2351 Australia
3. Biology Department; Indiana University; 1001 E Third St. Bloomington IN 47405 USA